Catalytic addition of compounds having a p-h bond to acetylene

ABSTRACT

Compounds containing a P-H bond add to acetylene in the presence of metal coordinating catalysts selected from groups VIA and VIII of the periodic table, to produce saturated organophosphorus compounds in good yields. The saturated organo-phosphorus compounds find utility as stabilizers, plasticizers and flame retardant additives for organic polymers, lubricating oils and hydraulic fluids.

finite States Lin atent [451 Aug. 1,1972

[54] CATALYTIC ADDITION OF COMPOUNDS HAVING A P-H BOND TO ACETYLENE [72] Inventor: Kingso Lin, Chingtsung, Newark,

Ohio

[73] Assignee: Hooker Chemical Corporation, Niagara Falls, N.Y.

[22] Filed: Nov. 12, 1969 [21] Appl. No.: 876,140

[52] US. Cl. ..260/970, 252/46.6, 252/49.8, 252/77, 252/400, 260/30.6 R, 260/45.7 P,

260/45.7 PS, 260/45.95, 260/429 R, 260/439 R, 260/438.5 R, 260/606.5 P, 260/932 [51] Int. Cl. ..C07f 9/40, C07f 9/00 [58] Field of Search ..260/970, 606.5 P

[56] References Cited UNITED STATES PATENTS 2,957,931 10/1960 Hamilton et al. ..260/970 X Primary Examiner-Joseph Rebold Assistant Examiner-Anton H. Sutto Att0rneyPeter F. Casella, Donald C. Studley, Richard P. Mueller, James F. Mudd and Richard K. Jackson 5 7] ABSTRACT 8 Claims, No Drawings CATALYTIC ADDITION OF COMPOUNDS HAVING A P-I-I BOND TO ACETYLENE BACKGROUND OF THE INVENTION The preparation of tetrabutyl ethylenediphosphonate has been accomplished by the addition of di-n-butyl phosphite to acetylene in the presence of a free radical catalyst (US. Pat. No. 2,957,931). Similar compounds have been prepared by the addition of a dialkyl phosphite to a dialkyl vinylphosphonate in the presence of a strongly basic catalyst (U.S. Pat. No. 2,651,656).

BRIEF DESCRIPTION OF THE INVENTION In accordance with this invention, it has been discovered that compounds of the formula:

in which R is a member of the group consisting of H, alkyl of one to 18 carbon atoms, alkoxy of one to 18 carbon atoms, and aryl of six to 12 carbon atoms, X is a member of the group consisting of oxygen and sulfur and n is an integer from to 1, can be prepared by a process which comprises reacting a compound of the formula:

in which R, X and n are defined above, with acetylene at a temperature between about 20 to about 200C. in the presence of a catalyst selected from the coordination forming metals of group VIA and VIII of the periodic table.

DETAILED DESCRIPTION OF THE INVENTION This invention relates to the catalytic addition of compounds containing a phosphorus-hydrogen (P-I-I) bond to acetylene (CH-CH) to produce two phosphorus-carbon bonds in a product having the structure in which the terms R, X and n defined above.

The catalysts found to be efiective in the reaction of this invention include salts and complexes of the transition metals which have been employed in the art as the catalysts for the addition and polymerization of acetylenic compounds.- The metal salts and their complexes are based upon the metals of groups VIA .and VIII of the periodic table. Especially applicable catalysts are the salts of iron, cobalt, nickel, ruthenium, rhodium, palladium, iridium, osmium and platinum, and their complexes. However, chromium, molybdenum and tungsten salts and their complexes may be employed under proper process conditions as the catalysts for the process of this invention.

The ligands which may be used in the metal complex catalyst for this invention include carbonyl, ammonia, alkylamines, arylamines, alkyl ene diamines, arylnitriles, alklnitriles, oximes, aldirnines. ketimines, arylazo compounds, alkylphosphines, arylphosphines, alkylphosphites, arylphosphites, dialkylformamides, and the like. The ionic ligands which may be used in the metalcatalyst for this invention are generally any salt of the transition metals, such as halides, carboxylates, sulfonates, phosphites, phosphates, cyanides, phenolates, thiophenolates, imides, alkylphosphides, acetylacetonates, isocyanates, thiocyanates, cyanates, isothiocyanates, and the like.

The formation of a coordination complex between a transition metal and a ligand such as acetylene or a compound containing a P-I-I bond may proceed directly or by substitution of new ligand for a ligand previously coordinated with the metal. For example, platinum and palladium chloride will enter directly into coordination complexes with acetylene. Chromium, molybdenum, tungsten, iron, cobalt, nickel, osmium and irridium form complexes with acetylenic unsaturation usually when other strongly pi-bonding ligands are present.

It is known that acetylene will enter into various types of coordinated complexes with transition metals (Advances In Organo Metallic Chemistry, Vol. 5, 1967, pp. 1 14-120). It is believed that the complex formation involved in the instant invention is either of the type in which acetylene becomes bonded to the metal and is still identifiable assuch, with the possible loss of one or moreof the original ligand groups of the parent molecule, or the. complex is the type obtained during the polymerization of acetylene.

The transition metal salts and their complexes employed in this invention generally form rather stable complexes with acetylene and a donor molecule containing the phosphorus atom. Because both acetylene and compounds containing the P-l-I bond are capable of acting as ligands in the formation of coordination compounds with transition metal salts, the catalytic species or the reactive intermediate may be regarded as either one or both of the acetylene and the phosphorus compound complexed through coordination bonds with the transition metal atom. As a result of the pibonding between the metal atom and acetylene, the later molecule becomes very reactive and susceptible to the addition of a molecule containing a nucleophilic atom.

Although applicant does not desire to be bound by any specific reaction mechanism, it is believed that the reaction of a compound containing a P-l-l bond with acetylene in the presence of a transition metal salt or complex proceeds by any one of the following paths in which M represents the transition metal, L represents a ligand and n is the number of complexed Us:

Path (1.) represents the formation of a coordination complexes, initial cis-addition and ultimate diaddition without legand displacement in the catalyst. Path (2.) illustrates the reaction mechanism which may take place with the displacement of a ligand from the transition metal complex. Path (3.) illustrates a reaction mechanism through which the reactant containing the PH bond enters directly into a coordination complex with the metal atom of the transition metal complex.

The pi-bonding between acetylene and the transition metal atom is evidenced from the fact that cis-addition occurs initially in the mono addition product.

Reactants of the type contemplated in the instant invention which contain a PH bond are those compounds embraced by the following formula:

in which R is an alkyl group of ll8 carbon atoms, alkoxy of l-l 8 carbon atoms, or aryl of 6-12 carbon atoms. X is oxygen or sulfur and n is from to 1.

More specifically, the reactants employed in this invention include dimethyl phosphine, diethyl phosphine, dipropyl phosphine, dibutyl phosphine, diamyl phosphine, dihexyl phosphine, diheptyl phosphine, dioctyl phosphine, dinonyl phosphine, didecyl phosphine, the corresponding dialkoxy phosphines, diphenyl phosphine, ditolyl phosphine and the corresponding primary and secondary phosphites and thio-phosphites.

The reaction of a compound containing a PH bond with acetylene to produce the diaddition product may be conducted in a suitable inert solvent. Representative inert solvents are the lower alkanols such as methanol, ethanol, propanol, etc; hydrocarbons such as alkanes of five to 18 carbon atoms, benzene, toluene, etc; ethers such as diethyl ether, dioxane, tetrahydrofuran, etc; nitriles such as acetonitrile, benzonitrile, etc; esters such as ethyl acetate, etc; amides such as dimethyl formamide; and the like. The reaction may be conducted in the absence of a solvent by the application of a suitable pressure to prevent the escape of gaseous reactants.

The temperature of reaction varies somewhat with the reactants but generally lies between room temperature and 200C. Preferably the temperature is between 40 to 180C. Generally, it is preferred that the reaction be conducted in the presence of an inert atmosphere which may be provided by nitrogen, argon, etc.

The reaction time necessary for a complete reaction will vary somewhat with the reactants, but generally the reaction may be completed within hours. A catalytic amount of the metal complexing agent (0.01 to about 1.0 mole percent) is sufficient to afford a high yield of the addition products. Preferably the amount of the catalyst used is 0.16 to about 0.32 mole percent.

P-JJ=OH- addition product which possibly serves as a weaker ligand than the initial reactant containing the PH bond. Thus, the PH ligand may serve as a strong ligand for formation of the metal coordination complex, blocking the reaction site from coordination to form the pi complex with the mono-addition product Friar and the transition metal.

The retarded reaction involved in the formation of the di-addition product may also be attributed to the decreased reactivity of the carbon-carbon unsaturation of the mono-adduct due to the interaction of the electrons in the d orbitals of phosphorus and the pi orbitals of the carbon-carbon double bond.

In any event, the formation of the diaddition product of acetylene and a reactant containing a PH bond takes place upon extended heating after formation of the unsaturated addition product, in the presence of an excess of the PH compound. Hence, the initial addition reaction may take from one to about 10 hours for an obvious decrease in the absorption rate of acetylene to occur. Generally from about 3 to 4 hours is sufficient to complete the first addition. After the recognition of reduced acetylene absorption occurs, the reaction mixture is maintained at the reaction temperature in the presence of an excess of the compound containing the PH bond for a period of from 1 to 10 additional hours to obtain the diaddition product in good yield.

I and are not to be construed as representing a limitation on the scope of the invention.

Reference to the transition metals in groups VIA and VIII, of the periodic table, supra, is based upon those groups as they appear in the Handbook of Chemistry and Physics, 32nd Edition, 1950-1951, Chemical Rubber Publishing Company. pp. 336-337.

EXAMPLE I A reaction mixture of grams grams of NiBr and 3.03 grams of tributyl phosphine was placed in a three necked flask equipped with a thermometer, reflux condenser and a sintered glass bubbler. The solution became dark purple in color upon heating at 100C for 20 minutes. Acetylene was then bubbled through the solution at a rate governed by the absorption of acetylene in the solution. The reaction temperature was maintained at from about 170 to 180C. After 5 hours of acetylene addition the reaction mixture was cooled to room temperature and distilled to give:

Fraction [-92.3 grams of a mixture of diethyl phosphite and diethyl vinylphosphonate having a boiling point l40C/0.5 mm;

Fraction 11-233 grams of material having a boiling point 140C/0.5 mm identified as tetraethyl ethylene diphosphonate; and 37.4 grams of residue.

Redistillation of fraction II gave tetraethyl ethylene diphosphonate of boiling point l18l20C/0.03 mm; m} 1.4419.

Elemental Analysis of fraction II; C H P O Calculated: C; 39.70, H; 7.95, P; 20.5 Found: C; 39.90, H; 7.86, P; 20.28 Molecular Weight Calculated 302 Molecular Weight Determined 305 The lR spectrum gave readings at 2,990, 2,940,

2,920, 2,880 cm (Cl-l, CH2 CH 1,425 cm (possible P- C), 1,255 cm (P 0).

EXAMPLE ll In a manner similar to that of example I, dioctyl phosphine, CH (CH PH was reacted with acetylene in the presence of (Cl-l CH CH Cl-l P) Ni(CO) to produce the diaddition product CH (CH )-,PCH CH P (CH2)7CH3. The addition did not take place below 180C. A slow reaction began at l85-190C. Distillation of the reaction mixture gave a 65 percent recovery of dioctyl phosphine and 35 percent of a material of boiling point 220C./0.05 mm. The IR spectrum of the distillation residue demonstrated the absence of PH and CH=CH absorption bands in the product ethylene bis-dioctyl phosphine.

EXAMPLE III A series of experiments were performed employing different PH containing reactants, acetylene and catalysts as follows:

Re- Vinyl- 0 Cataction time phosphonates other H alyst temp. hr. conyield products Run (5 O)2PH( g (3) version a R CH, (Bu P) NiBr 140-145 3 42 90 =2% di- (lSO) (4.63) addition product [2 R CH, (Bu P),

Ni(CO) 140-145 3 51 90 -2% di- (150) (4.35) addition product C R C H a NiB high boiling and diaddition product d R CgHn a )2 NiBr high

boiling and diaddition product e R a)2 H a )2 Ni(CO),165-170 3 =17 a p yacetylene Dialkyl phosphites were redistilled prior to the reaction but containing impurities: CH (85% purity) C H O (87%) and (CH CH (87%). The vinylphosphonates obtained were characterized from refractive index, elementary analysis and IR spectra. Conversions were calculated from G. C. data. Yields were calculated from the result of distillation. The IR spectrum of the polyacetylene produced in a run e indicated a highly crosslinked product containing phosphorus (2.1% P from elementary analysis). All the runs were carried out in a three necked flask equipped with a thermometer, a gas bubbler, a condenser and a stirrer at atmospheric pressure. By prolonging the reaction time while maintaining the recited reaction temperature, the yield of the diaddition product continues to increase.

EXAMPLE IV The following experiments were performed to illustrate the use of various ionic ligands. The catalyst NiX was employed in the addition of v o oinornoni n to ()IIECII at a reaction temperature of C. for 4 hours. The ratio of to NiX was 1.2 moles to 7.5 X 10' moles.

l H 55 (CII;CII2O)zi CH=OlI-2 (CH3CH2O)2l- CHZCHzP (0 011201102 Other (percent) (percent) percent Br 25 7.5 4.5 SCN' 28 3.8 2.0

J] 1 0113 011:0 CH; 38 7.5 3.4

in the order of acetylacetonate SCN* Br' l NO What is claimed is: 1. A process for the production of a compound of the formula:

in which R is a member of the group consisting of alkyl ing a compound of the formula: R P(X),,l-l in which R, X and n are defined above, with acetylene at a temperature between about 20C to about 200C in the presence of a catalyst selected from the group consisting of nickel bromide, nickel thiocyanate, nickel acetylacetonate, di(tributylphosphino) nickel bromide, di(tributylphosphino) nickel chloride, dicarbonyl (ditn'butylphosphino) nickel, dicarbonyl (triphenylphosphino) nickel, di(triphenylphosphino) nickel chloride, di(triphenylphosphino) nickel bromide, and

di(triphenylphosphino) nickel thiocyanate.

2. The process of claim 1 in which the temperature of the reaction is from about 40 to about 180C.

3. The process of claim 1 in which X is oxygen and n is l.

4. The process of claim 1 in which the catalyst is dicarbonyldi-(triphenylphosphino)nickel.

5. The process of claim 1 in which the catalyst is dicarbonyldi (tri-n-butyl phosphino)nickel.

6. The process of claim 1 in which the catalyst is di(tributylphosphino) nickel bromide.

7. The process of claim 1 in which R is alkoxy of one to 18 carbon atoms.

8. The process of claim 1 in which R is alkyl of one to 18 carbon atoms.

3 3 more smrrs PATENT orrict CE'HMQCATE Qt ECTEN Patent No. 3,68l +8l Dated August 1 l972 Inventofls) K1 ngso L1n It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column l, line 39 and Column 5, line 39, each occurrence "CH-=CH" sh uld r ad --CH CH--; Column 1, line 6l, "alklnitriles" should read --alkylnitriles-. Column 3, line l6, "legand should read --ligand Column 5, line 39 (Bu P) N1'(CO)' should read --(Bu P) N1'(C0) In the table appearing at Column 6, line 5 the heading ---X--- of the first column ---X-- should be inserted; Column 6, line 59 O O 0 O "CH C-CH=CCH should read -CH CCH CCH Column 7, line 3, "Nl" should read ---N1'---.

Signed and sealed this 9th day of January 1973.

(SEAL) Attest:

EDWARD MPLETCHERJR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents UNITED STATES PATENT OFFEQE cerrrimre r cc'ro Patent No. 3,681,L+81 Dated A g t 1, 1972 Inventor(s) Kingso Lin It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column l, line 39 and COlumn 5, line 39, each occurrence "CH=CH should read ---CH5CH--; Column l, line 6l, alklnitriles should read ---alkyln1'triles---. Column 3, line 16, legand should read ---ligand column 5, line 39 (Bu P) Ni((l0) should read ---(Bu P) N1'(CO) In the table appearing at Column 6, line 5 the heading --X--- of the first column ---X--- should be inserted; Column 6, line 59 O O O 0" H I II I "CH C-CH CCH should read --CH CCH=CCH Column 7, lin 3, "Nl" should read Ni---.

Signed and sealed this 9th day of January 1973.

(SEAL) Attest:

EDWARD M.PLETCHER,JR. Attesting Officer ROBERT GOTTSCHALK Commissioner of Patents 

2. The process of claim 1 in which the temperature of the reaction is from about 40* to about 180*C.
 3. The process of claim 1 in which X is oxygen and n is
 1. 4. The process of claim 1 in which the catalyst is dicarbonyldi-(triphenylphosphino)nickel.
 5. The process of claim 1 in which the catalyst is dicarbonyldi (tri-n-butyl phosphino)nickel.
 6. The process of claim 1 in which the catalyst is di(tributylphosphino) nickel bromide.
 7. The process of claim 1 in which R is alkoxy of one to 18 carbon atoms.
 8. The process of claim 1 in which R is alkyl of one to 18 carbon atoms. 